A device to device proximity service (English full name: Device to Device Proximity Service, D2D ProSe for short) between user equipment (English full name: User Equipment, UE for short) has become a hot issue in a Long Telm Evolution (English full name: Long Term Evolution, LTE for short) system.
D2D ProSe involves a data signal and an indication signal. The indication signal is used to indicate a physical resource occupied by the data signal, and the data signal is used to carry data. However, in an existing LTE communications system, the indication signal can randomly indicate only a frequency resource occupied by the data signal, and therefore, frequency selective fading cannot be effectively avoided, and a frequency diversity gain cannot be obtained.